Operating mechanism for vertically sliding door

ABSTRACT

The invention relates to operating mechanism for a vertically sliding door of a washing machine for laboratory equipment in which the door is raised to the open position by hydraulic pressure and is lowered to the closed position by gradually releasing the hydraulic pressure in such a way that during the downward run of the door the same is only under the influence of its own weight, so as to avoid accidental injury to the operator or damage to the equipment being washed.

United States Patent 119 Fillion et a].

[ 1 OPERATING MECHANISM FOR VERTICALLY SLIDING DOOR [75] Inventors:Paul-Henri Fillion, Ste-Foy, Quebec; Viateur Guay, Charlesbourg, Quebec,both of Canada [73] Assignee: Hoplab Inc., Quebec, Canada [22] Filed:Feb. 8, 1971 [21] Appl. No.: ll3,488

52 u.s.c1 ..49/360,49/139 511 1m.c1. ..E05f 15/08 [58] Field ofSearch..49/139,140,360 362;- 91/391; 92/172, 187; 98/115 LH; 312/209 [56]References Cited UNITED STATES PATENTS 546,854 9/1895 Holbrook etal.49/361, 2,844,967 7/1958 Leber ..92/l 87 X 111 3,714,737 1451 Feb. 6,1973 Primary Examiner-.l. Karl Bell Att0meyRaymond A. Robic 5 7 ABSTRACTThe invention relates to operating mechanism for a vertically slidingdoor of a washing machine for laboratory equipment in which the door israised to.

the open position by hydraulic pressure and is lowered to the closedposition by gradually releasing the hydraulic pressure in such a waythat during the downward run of the door the same is only under theinfluence of its own weight, so as to avoid accidental injury-to'theoperator or damage to the equipment being washed.

7 Claims, 6 Drawing Figures PATENTEU FEB 6 I973 SHEET 10F 2 A IN VENTORS Paul-Henri FILLION Viuteur GU Y PATENTEDFEB 6 I975 3.714.737 SHEET 20F 2 INVE NTORS 4 Poul-Henri FILLION Vioteur GUAY OPERATING MECHANISMFOR VERTICALLY SLIDING DOOR The present invention relates to operatingmechanism for a vertically sliding door.

The invention is particularly concerned with doors of washing machinesfor laboratory or medical equipment. Such machines are usually mountedin the wall between a controlled environment room such as a laboratoryor an operating room and the outside, and are provided with doors whichopen on opposite sides of the wall, so that soiled or unsterileequipment can be placed in the machine from the outside area with theinner door closed, subjected to a washing operation and then removedwhen needed from inside the controlled environment room with the outsidedoor closed or vise versa. This procedure minimizes the danger ofcontamination being admitted into the operating room or laboratoryduring time when it is essential to maintain aseptic conditions, whichtime coincides of course with periods when prompt and continuous supplyof equipment must be maintained.

Vertically sliding doors are preferably used in such machines becausethey require a minimum of space in relation to the size of the openingthey provide, they do not interfere with the loading and unloading ofthe machine and they insure a good seal around the door during thewashing operation.

Hitherto employed mechanical systems for the operation of suchvertically sliding doors have proved relatively unsatisfactory, however,because failure of essential parts of the mechanical system can lead tosudden dropping of the door and injury to the operator and damage to theequipment being treated. Because of the critical time factor involved insurgical operations, such accidents may have tragic results far beyondtheir immediate effect because of the time loss involved in repairingthe washing machine and replacing the damaged equipment.

The problem is made more acute by the fact that in order to withstandthe stresses imposed by the washing operation and to hold up underconstant use, the doors have to be sturdy and thus relatively heavy.

It is also difficult to keep the mechanical systems properly lubricateddue to their exposure to the washing fluid, all of which leads to faultyoperation.

The .conventional mechanical door opening devices have the furtherdisadvantage of complexity of design, which makes it likely for pocketsof fluid to be trapped within the mechanisms thus leadingto corrosion ofthe parts exposed as well as to dangerous septic conditions.

The present invention seeks to obviate the aforementioned disadvantagesof conventional mechanical systems by providing in their stead anoperating mechanism for vertically sliding doors of washing machines,whose functioning is entirely hydraulic.

The use of hydraulic means, furthermore, increases the safety of thesystem. In fact, should the operator accidentally place part of his orher body in the path of the descending door, such body part will thenonly have to support the weight of the door and no injury will resultbecause of the gentleness of the initial contact due to the gradualdescent of the door.

In accordance with the invention, the operating mechanism compriseshydraulic cylinders vertically mounted under the door, with a pistonmounted in each cylinder and a rod disposed between each piston and thedoor, the rods being arranged with their ends removably resting on thepistons.

The absence of a positive attachment between the rod and the piston inaccordance with the invention has the advantage of inherent simplicityof construction.

A further advantage is that the door can be raised manually withoutcarrying the piston along with it. This facilitates cleaning of the rodend and also makes it easier to open the door in case of failure of thehydraulic system from causes such as a drop in pressure or a stoppage inthe pipes.

A preferred embodiment of the invention is illustrated by way of examplein the accompanying drawings in which:

FIG. 1 is a perspective view of a washing machine for medical oflaboratory equipment having vertically sliding doors outfitted with anoperating mechanism according to the invention;

FIG. 2 is a vertical longitudinal fragmentary section of a hydrauliccylinder, piston and rod assembly and adjacent portion of the door;

FIG. 3 is a fragmentary horizontal cross-section of the door;

FIG. 4 is a diagrammatic plan of the washing machine cabinet mounted ina wall;

FIG. 5 is a schematic view of the hydraulic system in the rising oropening condition; and

FIG. 6 is a schematic view of the hydraulic system in the descending orclosing condition.

As shown in FIG. 1, the washing machine comprises a metal cabinet 10with side walls 11 and opposite front and rear walls 12 provided withremovable top and bottom panels 13 and 14 with an opening therebetweenin which fits a door 15.

Each door 15, as also shown in FIG. 3, consists of a tempered glasspanel 16 mounted in a metal frame 17 through the intermediary of agasket 18. The door 15 is provided with channels along its verticalsides which run in vertical slides 19 secured to the front and rearwalls 12 on either side of the opening and behind the top panel 13. Thedoors 15 are thus slidable between a topmost open position (shown indotted lines) and a bottom position in which they close the respectiveopenings of the front and rear walls 12.

FIG. 4 shows the washing machine cabinet mounted in the wall A of acontrolled environment room B such as an operating room or a laboratory,in such a way that soiled or unsterile equipment can be introduced froman outside area C by opening the door 15 on that side while leaving theopposite door 15 closed, treated in the washing machine with both doorsl5 closed, and then removed in the controlled environmentroom B byopening the door on that side while leaving the opposite door closed sothat direct contact with the outside can be completely avoided.

A control panel 20, mounted on the front wall 12, carries a plurality ofcontrol knobs, buttons and dials 21, some of which serve to direct thewashing operation, while others are for raising and lowering the doors15. A similar control panel (not shown) is provided on the rear wall 12.

The hydraulic system for raising and lowering the doors 15, with whichthe'present invention is particularly concerned, comprises for each door15 a pair of hydraulic cylinders 22 mounted vertically under the door 15on either side thereof behind the removable bottom panel 14, asillustrated in FIG. 1. Each cylinder 22 is open at the top as shown inFIG. 2 and contains a rubber or plastic piston 23 having at the bottom aflexible sealing flange 24 which is forced by hydraulic pressure againstthe cylinder wall.

Each piston 23 has on the upper face thereof a shallow hemisphericalsocket 25 in which rests the correspondingly rounded end of a rod 26.The upper end 27 of rod 26 is threaded and screwed into acorrespondingly threaded bore 28 opening onto the bottom face of thedoor 15. A nut 29 is mounted on the threaded end 27 of rod 26 and locksagainst the bottom face of door 15 once the projecting length of the rodhas been adjusted to a slightly greater dimension than the full slidingrun of the door 15.

The two cylinders 22 for each of the doors 15 are interconnected by across pipe 30. At the bottom of the cabinet 10, a supply pipe 31 (FIGS.and 6) feeds through a flow control valve 32 with an adjustable orificeand a solenoid actuated valve 34 into a connection pipe 35 opening intocross pipe 30. Downstream of the connection pipe 35 is a drain pipe 36also containing a solenoid actuated valve 37 and a flow control valve 38similarly provided with an adjustable orifice.

A branch with a supply pipe 39 having a solenoid actuated valve 40 and adrain pipe 41 having a solenoid actuated valve 42 is connected inparallel with valves 34 and 37 and in series with flow control valves 32and 38 and joins with a connecting pipe 43 feeding the cross pipe 30 forthe two cylinders 22 which operate the other door 15.

To raise and open either door 15, the corresponding valve 34 or 40 isopened while the corresponding valve 37 or 42 stays closed, wherebypressure fluid is admitted in equal proportion into the twocorresponding cylinders 22. Valve 34 or 40 can be closed to'hold thedoor in any desired position.

To lower and close either door 15, the corresponding valve 37 or 42 isopened while the corresponding valve 34 or 40 stays closed, whereby'thefluid in the corresponding cylinders 22 is forced and drained out ofthem by the weight of the door acting through rods 26 and pistons 23.

While the two doors can be operated independently because of theparallel arrangement of valves 34, 37, 40 and 42, the speed at whichthey open and close is adjusted collectively by setting flow controlvalves 32 and 38 respectively.

The operating members such as push-buttons or switches for valves 34, 40and for valves 37, 42 are preferably located on the control panels onthe sides of the cabinet of the corresponding'doors 15 which theycontrol, so that each door 15 can only be opened from the correspondingside of wall A.

For cleaning purposes, the doors 15 can be raised manually therebyexposing the ends of rods 26, and enabling removal of pistons 23.

The fluid fed to supply pipe 31 is preferably water at city systempressure which can thus be carried by drain pipe 36 to city systemdrains without the need of recirculation. This arrangement also obviatesthe necessity for any special power supply to operate the doors 15. Therequired connections to city water supply and drain present nocomplication since such connections are required in any case for theoperation of the washer.

In its open position, each door 15 trips a cut-off switch 44 whichrenders the washing system inoperative. Similarly, the washing systemmay include a cutoff switch (not shown) which prevents operation of thedoor opening valves 34 and 40 while the washing machine is in operation.A cut-off switch (not shown) may also be provided to limit the topmostposition of the door.

We claim:

1. Operating mechanism for a vertically sliding door comprising:

at least one hydraulic cylinder vertically mounted under said door,

a piston slidably mounted in said cylinder,

a rod disposed between said piston and said door,

a supply pipe and a drain pipe connected to said cylinder,

a first valve located in said supply pipe for permitting fluid to enterthe supply pipe when the first valve is opened so as to move said pistonupwardly and raise the sliding door, second valve located in said drainpipe for permitting said fluid to escape through the drain pipe underthe pressure exerted by the sole weight of the door acting on saidpiston when it is desired to lower the sliding door, and a control valvehaving an adjustable orifice located in both said supply and drain pipesso as to control the rate of opening and closure of the sliding door. 2.Operating mechanism for a vertically sliding door according to claim 1,wherein each piston has a shallow socket on the upper face thereof, andsaid rod end rests in said socket whereby the door can be raisedmanually without carrying the piston with it for cleaning the rod or inthe case of failure I of the operating mechanism.

3. Operating mechanism for a vertically sliding door according to claim2, wherein said socket is hemispherical, and

said rod end is correspondingly rounded. 4. Operating mechanism for avertically sliding door according to claim 1, wherein said rod isthreaded at its upper end, I said door has a corresponding bore openingon the bottom face thereof, said bore receiving said threaded rod endsopermit longitudinal adjustment of said rod. 5. Operating mechanism for avertically sliding door according to claim 4, wherein said threaded rodend has a nut mounted thereon locking against the bottom face of saiddoor. 6. Operating mechanism for a vertically sliding door according toclaim 1, wherein there are two such cylinders mounted at either side ofsaid door, said two cylinders being hydraulically interconnected. 7.Operating mechanism for a vertically sliding door according to claim 1,wherein said first and second valves are solenoid actuated valves.

1. Operating mechanism for a vertically sliding door comprising: atleast one hydraulic cylinder vertically mounted under said door, apiston slidably mounted in said cylinder, a rod disposed between saidpiston and said door, a supply pipe and a drain pipe connected to saidcylinder, a first valve located in said supply pipe for permitting fluidto enter the supply pipe when the first valve is opened so as to movesaid piston upwardly and raise the sliding door, a second valve locatedin said drain pipe for permitting said fluid to escape through the drainpipe under the pressure exerted by the sole weight of the door acting onsaid piston when it is desired to lower the sliding door, and a controlvalve having an adjustable orifice located in both said supplY and drainpipes so as to control the rate of opening and closure of the slidingdoor.
 1. Operating mechanism for a vertically sliding door comprising:at least one hydraulic cylinder vertically mounted under said door, apiston slidably mounted in said cylinder, a rod disposed between saidpiston and said door, a supply pipe and a drain pipe connected to saidcylinder, a first valve located in said supply pipe for permitting fluidto enter the supply pipe when the first valve is opened so as to movesaid piston upwardly and raise the sliding door, a second valve locatedin said drain pipe for permitting said fluid to escape through the drainpipe under the pressure exerted by the sole weight of the door acting onsaid piston when it is desired to lower the sliding door, and a controlvalve having an adjustable orifice located in both said supplY and drainpipes so as to control the rate of opening and closure of the slidingdoor.
 2. Operating mechanism for a vertically sliding door according toclaim 1, wherein each piston has a shallow socket on the upper facethereof, and said rod end rests in said socket whereby the door can beraised manually without carrying the piston with it for cleaning the rodor in the case of failure of the operating mechanism.
 3. Operatingmechanism for a vertically sliding door according to claim 2, whereinsaid socket is hemispherical, and said rod end is correspondinglyrounded.
 4. Operating mechanism for a vertically sliding door accordingto claim 1, wherein said rod is threaded at its upper end, said door hasa corresponding bore opening on the bottom face thereof, said borereceiving said threaded rod end so as to permit longitudinal adjustmentof said rod.
 5. Operating mechanism for a vertically sliding dooraccording to claim 4, wherein said threaded rod end has a nut mountedthereon locking against the bottom face of said door.
 6. Operatingmechanism for a vertically sliding door according to claim 1, whereinthere are two such cylinders mounted at either side of said door, saidtwo cylinders being hydraulically interconnected.